1 // run-pass 2 #![allow(unused_variables)] 3 // Test that you can supply `&F` where `F: FnMut()`. 4 5 #![feature(lang_items)] 6 a<F:FnMut() -> i32>(mut f: F) -> i327fn a<F:FnMut() -> i32>(mut f: F) -> i32 { 8 f() 9 } 10 b(f: &mut dyn FnMut() -> i32) -> i3211fn b(f: &mut dyn FnMut() -> i32) -> i32 { 12 a(f) 13 } 14 c<F:FnMut() -> i32>(f: &mut F) -> i3215fn c<F:FnMut() -> i32>(f: &mut F) -> i32 { 16 a(f) 17 } 18 main()19fn main() { 20 let z: isize = 7; 21 22 let x = b(&mut || 22); 23 assert_eq!(x, 22); 24 25 let x = c(&mut || 22); 26 assert_eq!(x, 22); 27 } 28